LED (light emitting diode) lighting is increasingly used today especially in automotive applications. Especially automotive signaling lamps, such as tail lamps, turn lamps and stop lamps, commonly referred to as rear combination lamps (RCL) and daytime running lamps (DRL) are today realized with a plurality of LED elements.
LED elements require mechanically stable mounting, electrical connection and heat dissipation. These functions are especially well fulfilled by clinch frame technology. In an article “HP SnapLED: LED assemblies for automotive signal lighting” in The Hewlett-Packard Journal Volume 50, Number 1, Article 1, Nov. 1, 1998 by James Stewart this technology is explained. A clinch frame is manufactured from a flat metal sheet material (copper alloy with tin alloy plating). LED elements, termed SnapLED are mounted on the clinch frame by a clinching operation, which is a method for mechanically joining two metal sheets by deforming the sheet material between opposing tools, a punch and an anvil. The LED elements may thus be arranged in an array on the leadframe, which subsequently may be formed by bending the leadframe material to a desired shape conforming to the geometry of the vehicle.
However, in present lighting assemblies using LEDs, optical functionality, i. e. the forming of a desired beam shape of the light emitted from the LED elements is generally achieved by separate optical elements, such as e. g. parts of the LED packaging serving as lenses etc.